Creating triangle shaped percentage graph with C#

[Angela]

I am using VS.NET 2003 and Crystal 9. I have been told by Crystal, as
well as many co-workers who know Crystal really well, that I cannot
create the particulat graph I need using Crystal Reports.

Here is an example of the kind of data I am trying to graph:
Question: How much TV people watch a day?
Responses (as a percentage of total responses):

2.0 hours = 60%

2 - 4 hours = 30%
< 4 hours = 10%

I need to create a graph that is shaped like a triangle, with the
triangle representing the total of 100%. I need to have that graph
show what portion of the total each of three subgroupings represent.
So the graph should be a single triangle made up of 3 colors. Each of
those colored sections represents one of the groupings above (60%, 30%
ans 10%). It essentially looks like a 2-Dimensional candy corn - for
lack of a better visual.

I can probably use the Drawing class to do this, but has anyone
already had a similar problem and already come up with the algorithm
to do this? Just trying to save some time if possible.

Angela